How to troubleshoot events in the Windows Event Logs?

For the other part of your question: The 0x43 in windows networking world means "The network name cannot be found" 0x43 = Decimal 67. So if you look up windows error code 67, you'll get this up.

I must say that this is one of those times when we'll have to sit and analyze the issue for a good time. I'd probably do the following in this case:

1. Examine the errors and establish a pattern(like are they occuring after a specific event, like during start up, shutdown, start up of an application, etc.) and then try to narrow down the list of possible culprits.
2. I will also try to isolate it further by checking if its specific to this user(have another user login to the same box), or specific to this machine(have this user login to another box).
3. Then use the tools to capture the invisible details: procmon, procexp, tcpview, windbg etc., until the event occurs again, and then look at the info. I usually find something here(success rate > 75%)
4. possibly something else based on the above three steps.

Of course, I'll keep using Google; hey it's an extension of our brains, no?

The ideal approach in the troubleshooting world has to be isolate-and-conquer. Hope I made some sense.

I don't know of any sites offering this info and wait to be corrected. However answering your in a general way is say - this is where your skills as fault finder come into play.

i'd start by searching for key words, NlaSvc for example. Then possibly identifying the interface - maybe going to search for other log messages. All in all its a hunt the thimble game and you'll get better at it as you do more.

PS. I'm not saying you haven't done this - but this is how I'd approach a problem like this.

Put it into google, put parts of it into google, find associated information and repeat.

For your second question, try http://eventid.net

They have comprehensive info about almost every error logged in the event viewer.